Iron annealing receptacle



IRON ANNEALING RECEPTACLE' Filed March 3l, 1957 2 SheebS--Sheei'I im? l film Mmm,

E25/Vm ef dit Patented Aug. z, 193s EFTA en, Grey 937 r No. 134,175

t r' d, 1936 auch tbi ir na, in 'a neavv load due to tbe ticies er. however., tbe

m result t time bores are comparativelv ireavv d at eacb traum the large mass ci the bor bas to be heated up. addition i ,it to time presence or ormaen ere ia a consi erable ioation oi ace on tbe nes at each heating and coo. e resnlt is a ,comparatively lona mi oi anneaiina and a rapid deterioration of tbe bones vvbich considerably increa the nea coattae it ia on account voi there disadvantages that vor com@ time bones have been made oi refractory metal d vvitii comparatively tiiin nails. Sucio bones however, are e damaged during manipulation., for enple, vvhenbeing removed iront the t: eaiing furnace. Moreover, the refractory metal is very sensitive to thin dames and tbesulpbur contained therein so that the length oi life oi the boxes and tbe operating costs are detrinientaily aeoted. i

lit iras already been proposed to avoid the action oi tire neatina gasses on the annealing bores and tbe scaling thereof due to contact vvitii the airv by screening the bon with a protecting jacket oi beat resisting sheet etal. This irnovvn soreening however. again leads to tbicesses oi the aealing bor vvali winch have a detrimentai edect on themanipulation and the operation, that is, rapid bea and cooling oi the box. also a protective jaciret oi beat resist sheet` metal is vers,r sensitive to t dames am` the sulphur cont ed therein d therefore will lise-li be deetroved in a comparatively snort time.

'in order to avoid these drawbacks and also to obtain the advtaae oi t walled annealreceptacies accorg to tbe invention the t Walled receptacle, for eaampie, anealing boit, an anneag ho or pot and tire iiire, is surrounded by a protective covering in the io oi a nett/vorn, ior mi oi ended metal which protects the receptacle t damaire. l'libe edect oi protective covering is tartiner improved according to the invention by the meshes ci the network being nlied with a material oi nood the conductivity which at the :i e time afiordsreliable protection against 55 ioation of scale and corrosion oi ytire receptacle.

account oi this covering of the receptacle ita total wall thickness is brought to a size which ie very iavorable ior practical purposes.

e teriai for the covering is preferably Nichrotherm, alloy of highV melting point which resists scale and corrosion and ensures rapid heating and cooling of the receptacle. The tilt ior the meshes is preferably refractory 4clav or any other suitable substance with good eal conductivity.

veral constructional examples of the invention are illustrated in the accompanying drawinae., l

Vil. shows an annealing box in axial section.

Fie. Z is a side elevation.

Fig. il is a cross section.

Flr. ii siio'tvs a iurther construction of an annealing bon according to the invention 'in axial section.

Fig. 5 is a side elevation. 20

Fig. o shows an annealing hood or box provided with the protective covering according to the invention in longitudinal section.

Fig. 7 is a cross section.

a is the annealing receptacle proper of cast steel, wrought iron or of a specially heat resisting metal. b is a net-like protective covering 'which is made of ordinary wrought iron or preferably ci a metal which resists scale and corrosion, for example, Nichrotherm. The meshes of the net-like protective covering are filled with a nre resisting material c of good thermal conductivitv.

iin-order to protect the covering on the bot- Atrim of tine annealing box from damage the bottom of the box can be suitably set back as shown in Figures t and 5, with respect to a supporting edge a1 in order to form a cavity in which the covering is placed. Obviously the provision of the protective covering according to the invention is not limited to the annealing receptacles illustrated but is also applicable to any type of annealing receptacle.

l. .an external protective covering for an iron ealing receptacle. Aconsisting of a network oi expanded metal and a refractory material of goed thermal conductivity lling the meshes of the network.

d. a iron annealing receptacle having an external protective covering constructed in the form oi a network of expanded metal and a supDOiting edge around the bottom of the container'for io wv a depression ln which the protective cove may be placed.

r'RmDRIcH Bamm. 

